Although it is often said that the common cold is the most prevalent disease among humankind, it is also true that chronic pain is an affliction that is almost as prevalent. Chronic headaches, muscle pain, joint pain, and the like are experienced by most individuals, and many persons have such chronic pain on a daily or weekly basis.
It is interesting to note that most forms of chronic pain often are not traceable to a specific causative factor. The term "referred pain" has been used to describe pain that is experienced at a locus removed from the cause or lacking an identified cause. From the perspective of a treating physician, this situation leads to skepticism concerning the patient's complaints, and a tendency to dismiss the complaints as psychosomatic, neurological, or imagined. From the perspective of the patient, there is real suffering experienced on a regular basis, and often there is no medical treatment to relieve the pain. Frequently, medical treatment consists of drugs such as analgesics or muscle relaxers. These substances are systemic, and can have adverse side effects such as kidney toxicity, liver inflammation, gastrointestinal symptoms, and the like. Alternative treatments consist of chiropractic manipulations, acupuncture, physical therapy, stress relief regimens, and the like. These approaches to treatment have had limited success for most chronic pain sufferers.
Research conducted 40 to 50 years ago indicated that referred pain could be emulated in test subjects by injecting hypertonic saline solution into the interspinous ligaments and causing temporary inflammations of the periosteum at the points where muscle tissue extends from the upper spinal vertebrae to the skull and the scapula. Referred pain was produced at various sites remote from the injection points, and was virtually indistinguishable from the sensations described by chronic pain sufferers. Moreover, it was clear that induced inflammation of specific sites along the spinous processes resulted in pain sensation at corresponding specific sites throughout the body far removed from the cause, and that the pain sensation could also be induced in the form of headaches similar to migraine headaches. This research also established that the pain referral mechanism did not involve mere neural transmission. However, this promising early work apparently was not followed, and did not result in effective treatment modalities.
In recent years low power lasers have been introduced for pain relief. Generally speaking, low power lasers have been used to treat "trigger points"; i.e., neural pathways that serve the area in which the pain is experienced; or to treat directly the muscle, joint, or area in which the pain is experienced. Low power lasers have also been used to treat the traditional acupuncture points. These treatment approaches do not take into account the fact that referred pain is linked to a causative factor far removed from the site of the pain, and that the referred pain sensation is not transmitted by neural action. Low power lasers have enjoyed some success, but the potential for this treatment modality has not been realized due to a lack of consideration of the root cause of referred pain.